Signal and OldSignal have conflated docs

[alex-y-z]

These classes share an API page as a result of a naming collision. According to their Moonwave comments, Signal.lua defines GoodSignal, and OldSignal.lua defines Signal.

However, "Signal" is the actual class/table name in both files, so their members are aggregated under Signal, and GoodSignal exists as a member-less page.

Additionally, OldSignal attempts to redirect to GoodSignal, which doesn't exist given the current file name.